import { Injectable, Injector } from '@angular/core';
import { Observable, Subscriber } from 'rxjs';
import { HttpClient, HttpErrorResponse, HttpHeaders, HttpParams, HttpResponse } from '@angular/common/http';
import { Router } from '@angular/router';
import { TokenService } from '../interceptor/token/token.service';

const TYPE = {
    ERROR: 'error',
    WARNING: 'warning',
    SUCCESS: 'success'
};

@Injectable()
export class HttpUtils {


    _options = {
        observe: 'response',
        responseType: 'json'
    };
    _messageId;
    private _loading = false;

     /** 是否正在加载中 */
    get loading(): boolean {
        return this._loading;
    }

    private parseParams(params: any): HttpParams {
        let ret = new HttpParams();
        if (params) {
            for (const key in params) {
                if (params[key] !== undefined) { // 如果是undefault不传
                    const _data = params[key];
                    // // 将时间转化为：时间戳 (秒)
                    // if (moment.isDate(_data))
                    //     _data = moment(_data).unix();
                    ret = ret.set(key, _data);
                }
            }
        }
        return ret;
    }

    private request<T>(method: string, url: string, options?: RequestOption): Observable<HttpResponse<T>> {
        const opt = this.options(options);
        const myObservable = this.http.request(method, url, opt);
        return Observable.create((observer: Subscriber<HttpResponse<T>>) => {
            myObservable.subscribe({
                next: (response: HttpResponse<T>) => {
                    observer.next(response);
                },
                error: (response: HttpErrorResponse) => {
                    // this.handleError(opt, response);
                    observer.error(response);
                },
                complete: () => { // 发错误了之后不跳complete了
                    observer.complete();
                }
            });
        });
    }

    // private handleError(opt, response: HttpErrorResponse) {
    //     if (opt.handleError) {
    //         switch (response.status) {
    //             case 400: {
    //                 const error: any = response.error;
    //                 this.error(error.error_description, TYPE.ERROR, opt.autoMessage);
    //                 if (error && error.code === 'invalid_token') {
    //                     this.goLogin();
    //                 }
    //                 break;
    //             }
    //             case 401: {
    //                 let message = 'Unauthorized';
    //                 let type = TYPE.ERROR;
    //                 if (response.error.error === 'invalid_token') {
    //                     message = 'Session expired, please log in again.';
    //                     type = TYPE.WARNING;
    //                 }
    //                 this.error(message, type);
    //                 this.goLogin();
    //                 break;
    //             }
    //             case 403: {
    //                 this.error('Forbidden');
    //                 break;
    //             }
    //             case 500: {
    //                 if (response.error && response.error === 'invalid_token') {
    //                     this.error('Unauthorized');
    //                     this.goLogin();
    //                     break;
    //                 }
    //                 this.error('Internal Server Error');
    //                 break;
    //             }
    //         }

    //     }
    // }

    private options(options: RequestOption) {
        return Object.assign({ handleError: true }, options, this._options);
    }

    private error(message, type = TYPE.ERROR, display: boolean = true) {
        if (!display) {
            return;
        }
        // 一秒钟内，多个请求只出错，只提示第一个错误
        if (!this._messageId) {
            // this._messageId = this.injector.get(NzMessageService).create(type, message); // 提示错误信息
            setTimeout(() => {
                this._messageId = null;
            }, 1000);
        }
    }

    get<T>(url: string, params?, options: RequestOption = <RequestOption>{}): Observable<HttpResponse<T>> {
        options.urlParams = this.parseParams(params);
        return this.request<T>('get', url, options);
    }

    post<T>(url: string, body?, options: RequestOption = <RequestOption>{}): Observable<HttpResponse<T>> {
        options.body = this.parseParams(body).toString();
        options.urlParams = this.parseParams(options.urlParams);
        return this.request<T>('post', url, options);
    }

    put<T>(url: string, body?, options: RequestOption = <RequestOption>{}): Observable<HttpResponse<T>> {
        options.body = this.parseParams(body).toString();
        options.urlParams = this.parseParams(options.urlParams);
        return this.request<T>('put', url, options);
    }

    delete<T>(url: string, body?, options: RequestOption = <RequestOption>{}): Observable<HttpResponse<T>> {
        options.body = this.parseParams(body).toString();
        options.urlParams = this.parseParams(options.urlParams);
        return this.request<T>('delete', url, options);
    }

    form<T>(url: string, options: RequestOption = <RequestOption>{}): Observable<HttpResponse<T>> {
        options.urlParams = this.parseParams(options.urlParams);
        options.body = this.parseParams(options.body).toString();
        const header = new HttpHeaders({ 'content-type': 'application/x-www-form-urlencoded' });
        const merge = Object.assign({}, options, { headers: header });
        return this.request<T>('post', url, merge);
    }
    /**
     * formData 上传文件
     * @param url 地址
     * @param data 选择的文件
     */
    upload(url: string, data: any) {
        const token = this.tokenService.access_token.access_token;
        const xhr = this.createXHR();
        const formData = new FormData();
        formData.append('file', data);
        const p = new Promise(function (resolve, reject) {
            xhr.open('POST', url, true);
            xhr.setRequestHeader('Authorization', `Bearer ${token}`);
            xhr.onreadystatechange = function () {
                const resultObj = xhr.responseText ? JSON.parse(xhr.responseText) : xhr.responseText;
                if (xhr.readyState === 4) {
                    if (xhr.status >= 200 && xhr.status < 300) {
                        resolve(resultObj);
                    } else {
                        reject(resultObj);
                    }
                }
            };
            xhr.send(formData);
        });
        return p;
    }

    private createXHR() {
        let xhr = null;
        if (XMLHttpRequest) {
            xhr = new XMLHttpRequest();
        }
        return xhr;
    }

    private goLogin() {
        // this.injector.get(SettingsService).clean();
        this.injector.get(TokenService).destroy();
        this.injector.get(Router).navigate(['/login']);
    }

    constructor(private http: HttpClient, private injector: Injector, private tokenService: TokenService) {

    }

}

export interface RequestOption {
    body?: any;
    headers?: HttpHeaders;
    reportProgress?: boolean;
    observe?: 'response';
    urlParams?: HttpParams;
    responseType?: 'json';
    withCredentials?: boolean;
    handleError?: boolean;
    autoMessage?: boolean;
}
